If you would prefer to control our USB attenuator or USB RF switch models using Python instead of our standard Windows based GUI test program, JFW does offer a Python library (jfwusb.py). Email our engineering department for the Python library and examples.

Python Library Features:

Auto-discovery of any JFW USB devices connected to the computer.

Set persistent device names for each attenuator.

Set/read attenuator by its device number.

Set/read attenuator by its serial number.

Set/read attenuator by its user defined name.

Set all attenuators to the same dB value, min dB value, or max dB value.

JFW model 50BA-032-31 SMA is a 4 channel attenuator assembly that covers 0.1-18 GHz. Each channel consists of a solid-state programmable attenuator with attenuation range 0 to 31dB in 1 dB steps. Each attenuator can be controlled individually or as a group. This benchtop attenuator assembly is remotely controlled via Ethernet/RS-232 and manually via momentary toggles on the front panel.

The current attenuation setting for each attenuator is displayed on the front panel. Whether the attenuators are changed by a remote user or manually, the attenuation displayed will be updated immediately. This is very useful when running remote scripts so that you can see that attenuator settings changing as the script executes.

The application note is an introduction to programmable attenuators and their applications. If you would like to discuss your application with our engineering staff please call (1-317-887-1340) or email.

JFW is proud to announce the addition of a new line of 18 GHz step attenuators to our product line. These new 50 Ohm solid-state step attenuators cover 100 MHz to 18 GHz with an attenuation range of 0-31 dB by 1dB steps. The attenuators can handle up to +20 dBm of RF input power. We offer these attenuators as individual components or as an integrated RF test system.

Why use a USB Attenuator?

In RF test labs, programmable attenuators and RF switches are a basic building block of performance testing. Programmable attenuators are used in fading, handover, and rate vs range testing. Among other things, RF switches are used in signal routing, component bypassing and switched filter banks. To fill this need, JFW offers an expansive selection of Programmable Attenuator Assemblies and RF Switch Assemblies in 19″ rack or benchtop enclosures. These boxes typically include Ethernet and RS-232 control. While appropriate for medium to large testing environments, a USB Attenuator or USB RF Switch is often a better solution for smaller test setups. Lower cost and smaller size of the USB device are especially relevant.

Now available from JFW: USB Programmable Attenuators with 0.25 dB & 0.5 dB step size up to 3 GHz. The majority of programmable attenuators available have 1 dB steps. However, for some applications, such as satellite communication testing, smaller step sizes can be beneficial. For those cases, these three models can provide that capability.

New Models

All three attenuators are controlled and powered through a Mini-B USB connector. A USB hub can be used to simultaneously control multiple attenuators. Included with each step attenuator is our Windows-based GUI software for easy attenuation control of a single or multiple attenuators.